'88 TBI Build

[bucket]

Manifolds that fit the bolt pattern of Vortec heads don't have a heat crossover. The manifolds are designed for a "dry" system meaning they use port fuel injection. The manifolds only flow "dry" air, not air mixed with fuel like you have with TBI or carb. When wet air encounters a sharp angle, i.e. an abrupt change in direction, the fuel separates from the air due to different densities. Cold manifolds condense air/fuel mixtures. When the charge hits the bottom of the manifold it has to make a 90 degree turn. This is where the separation occurs. This is also why you will see a waffle pattern cast into the manifold at this location. A manifold with a heat crossover helps keep the fuel/air charge in a vapor (lighter) state and less prone to separation. Think filters that spin the air to separate dirt particles, same for canister vacuums. Same principle. Vortecs are ok once warm but a PITA when cold. This gets annoying on a daily driver. Hope this helps.

Right, I know all that. But my point is, many people such as myself daily drove SBC's that did not employ a heat crossover and nobody complained about it.

Many aftermarket heads do not have a heat crossover. Many people with stock heads have run intake gaskets that block the heat crossover. Unless I'm missing something, that is no different than running vortec heads (I've done that too).

 

[Ricko1966]

@bucket I wish I had an answer,I wish I knew myself. I've had bad luck, @squareroots had bad luck, some people never have a problem. Some never have a problem with no starter brace,some do. Some people put in any hei no problem @SirRobyn0 will tell you he can't get away with it. I think it's just a ton of varibles,humidity,temperature,cam profile,compression,timing,on and on and on. They may work fine for one but not for all. Just a little example I was repairing a sand car for a customer it was a super charged 3800 buick that grenades any magazine super transaxle he put in it. I built 1 transmission out of 3 and sent him on his way. Three years later he came back can you build me another transmission. I was you couldn't blow the transmission up with clutch I put in it. Yea that clutch started slipping in 3rd gear so I put a 2500lb pressure plate in it. 1 part changed changed everything.

 

[Powerhouse Ranch]

Thank you for all of the wise words here gentleman. I've been pushing it around and had lengthy conversations with a good deal of experienced folks in person as well past few days. Looks like i'll be doing the Vortec heads. Might we consult this literature for a moment as well (one of my many sources next to you guys)

https://www.motortrend.com/how-to/make-power-with-gm-tbi-throttle-body-injection/

For my possible setup, it appears Jegs carries the majority of this. Their "Edelbrock Small Block Chevy T.B.I Performer Power Package", not an official kit that i can find entirely, doing more research. But LOOKING like the Vortec heads paired with the performer TBI intake. It also suggests a cam as well. In the description is for the manifold it states: "No chip changes or computer mods required unless entire 5.7L Power Package (manifold, cam, heads) is used. Computer chip is supplied free of charge with proof of purchase of manifold, cam and heads. The chip re-programs your computer for optimum power gains when the entire package is installed. This Total Power Package greatly improves performance." This is step i'd be willing to take.

With the advice of my father who's seen the power of these heads, i'm thinking this is will be the route. Especially since my passenger head has been discovered as warped. Makes sense. @SquareRoot, @Ricko1966, @bucket, and others all make good points. I'll be looking for all of these possible scenarios and keeping these in mind. How i tend to run my rigs (except the '87 dump) is to run them in the spring/summer/fall and let sit for winter away from the dreaded Pennsylvania road salt. So i won't be dealing too much with the cold weather PITA side of things.

I also intend to keep the factory TBI. It ran well and the truck is already complete and set up well for this system. Not to mention i've already purchased new items for this system (IAC, TPS, etc.) I'd really hate to have this truck down even longer just to pull the tank again and update fuel senders and do alot of rewiring that i'm practically wrapping up on. I think i'm going to take my chances on the system and see what it can do, and if anything, i'll be a proven try that we can all reference, for the good or the bad. I can always change down the road, that's the beauty of mechanics.

Another note, don't know if any of you CUCV guys deal with Hillybilly Wizard, but I'm really satisfied with what he does. Just my 2 cents. . .

 

[SquareRoot]

Maybe the egr compensated for the lack of heat crossover? Like Ricko said, luck of the draw I guess.

 

[SquareRoot]

Thank you for all of the wise words here gentleman. I've been pushing it around and had lengthy conversations with a good deal of experienced folks in person as well past few days. Looks like i'll be doing the Vortec heads. Might we consult this literature for a moment as well (one of my many sources next to you guys)

https://www.motortrend.com/how-to/make-power-with-gm-tbi-throttle-body-injection/

For my possible setup, it appears Jegs carries the majority of this. Their "Edelbrock Small Block Chevy T.B.I Performer Power Package", not an official kit that i can find entirely, doing more research. But LOOKING like the Vortec heads paired with the performer TBI intake. It also suggests a cam as well. In the description is for the manifold it states: "No chip changes or computer mods required unless entire 5.7L Power Package (manifold, cam, heads) is used. Computer chip is supplied free of charge with proof of purchase of manifold, cam and heads. The chip re-programs your computer for optimum power gains when the entire package is installed. This Total Power Package greatly improves performance." This is step i'd be willing to take.

With the advice of my father who's seen the power of these heads, i'm thinking this is will be the route. Especially since my passenger head has been discovered as warped. Makes sense. @SquareRoot, @Ricko1966, @bucket, and others all make good points. I'll be looking for all of these possible scenarios and keeping these in mind. How i tend to run my rigs (except the '87 dump) is to run them in the spring/summer/fall and let sit for winter away from the dreaded Pennsylvania road salt. So i won't be dealing too much with the cold weather PITA side of things.

I also intend to keep the factory TBI. It ran well and the truck is already complete and set up well for this system. Not to mention i've already purchased new items for this system (IAC, TPS, etc.) I'd really hate to have this truck down even longer just to pull the tank again and update fuel senders and do alot of rewiring that i'm practically wrapping up on. I think i'm going to take my chances on the system and see what it can do, and if anything, i'll be a proven try that we can all reference, for the good or the bad. I can always change down the road, that's the beauty of mechanics.

Another note, don't know if any of you CUCV guys deal with Hillybilly Wizard, but I'm really satisfied with what he does. Just my 2 cents. . .

Do we dare discuss the water bypass issue with Vortec heads now? Lol

 

[Powerhouse Ranch]

Do we dare discuss the water bypass issue with Vortec heads now? Lol

Oh boy. We might as well. What do you got

 

[SquareRoot]

Oh boy. We might as well. What do you got

I'll take the easy way out on this one. Type in "Vortec bypass hose" in the search block. Even @bucket has indulged in the conversation.

 

[Frankenchevy]

I, too, had drivability issues with running vortec manifolds wet. Unlike Mike, I had a good experience with the Sniper, up until the first colder winter morning.

With ambient temps here in the mid 20s first thing in the AM December to mid February, the manifold air temp (MAT) would be in the teens to low 20s. The first morning, it sputtered and bucked through the first ten or so minutes, until the manifold warmed sufficiently.

The next morning I fired it up, same thing. I shut it down and looked down the barrels. There was slight condensation in the barrels and pooling in the waffle at the bottom of the manifold.

It was better to fire the truck hop in and go, with minimal warmup. Letting the truck warmup seemed to exacerbate the sputtering for the first several minutes of driving. I watched the MAT drop several degrees in the first few minutes due to air velocity and the cooling effect of the fuel.

This condition was present to some extent up to about 40 degree ambient temps. Obviously the warmer it was up to that point, the less symptomatic it would be. Could this be tuned out, possibly… Just like choke on a carb, the Sniper will richen up the AFR on a cold start. I tried lowering that on the software table, but you end up with other issues as a result.

It is possible that a different manifold could be the solution, but at that point my mind had already moved on to MPFI. I’d read several accounts of carbed guys having similar issues in their newly vortec headed muscle cars. It was the junkyard head du jour for several years prior to LS dominance.

Every combination is a little different though. Obviously, this is only an issue when it gets decently cold out. Maybe you’ll be one of the lucky ones with no issues. As far as Vortec heads go, I wouldn’t get too hung up on them. Watch the Engine Masters episode about heads that was put out recently. I’d spend a bit more money and get some AFRs. Look at which piston was installed and figure out piston to valve clearance after deciding on the cam and other components. Might also be worth double checking the work that was done on the bottom end too.

 

[Catbox]

More for you to look into....

EBL SFI-6 Flash

You must be registered for see images attach

 

[SquareRoot]

I, too, had drivability issues with running vortec manifolds wet. Unlike Mike, I had a good experience with the Sniper, up until the first colder winter morning.

With ambient temps here in the mid 20s first thing in the AM December to mid February, the manifold air temp (MAT) would be in the teens to low 20s. The first morning, it sputtered and bucked through the first ten or so minutes, until the manifold warmed sufficiently.

The next morning I fired it up, same thing. I shut it down and looked down the barrels. There was slight condensation in the barrels and pooling in the waffle at the bottom of the manifold.

It was better to fire the truck hop in and go, with minimal warmup. Letting the truck warmup seemed to exacerbate the sputtering for the first several minutes of driving. I watched the MAT drop several degrees in the first few minutes due to air velocity and the cooling effect of the fuel.

This condition was present to some extent up to about 40 degree ambient temps. Obviously the warmer it was up to that point, the less symptomatic it would be. Could this be tuned out, possibly… Just like choke on a carb, the Sniper will richen up the AFR on a cold start. I tried lowering that on the software table, but you end up with other issues as a result.

It is possible that a different manifold could be the solution, but at that point my mind had already moved on to MPFI. I’d read several accounts of carbed guys having similar issues in their newly vortec headed muscle cars. It was the junkyard head du jour for several years prior to LS dominance.

Every combination is a little different though. Obviously, this is only an issue when it gets decently cold out. Maybe you’ll be one of the lucky ones with no issues. As far as Vortec heads go, I wouldn’t get too hung up on them. Watch the Engine Masters episode about heads that was put out recently. I’d spend a bit more money and get some AFRs. Look at which piston was installed and figure out piston to valve clearance after deciding on the cam and other components. Might also be worth double checking the work that was done on the bottom end too.

Excellent summary. I also would not go with Vortec heads again. I think the AFR 195's are shizz these days.

 

[Powerhouse Ranch]

Excellent summary. I also would not go with Vortec heads again. I think the AFR 195's are shizz these days.

Alright, give me the run down on those. What's that system like? Decent with TBI? Is there a TBI intake for these heads? etc.

 

[Ricko1966]

Here ,you go. Better than vortec,better flow,no machine work for big cam standard chevy intakes.

Eight Budget Small Block Chevy Heads Tested

We compare and contrast eight budget small block Chevy heads.

www-motortrend-com.cdn.ampproject.org

Airflow Research (AFR) 1006 AFR 195cc SBC Enforcer Cylinder Heads | Summit Racing

Free Shipping - AFR 195cc SBC Enforcer Cylinder Heads with qualifying orders of $109. Shop Cylinder Heads at Summit Racing.

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[SquareRoot]

The AFR's are better than vortecs in every way. Cost is almost a wash. Intake manifold is cheaper. I don't know (anybody?) if TBI has the traditional 4150 mounting flange like the carbs and aftermarket TBI?
Do a search on YouTube for the AFR vs Vortec heads. There are literally tons of demonstrations.

 

[Powerhouse Ranch]

Here ,you go. Better than vortec,better flow,no machine work for big cam standard chevy intakes.

Airflow Research (AFR) 1006 AFR 195cc SBC Enforcer Cylinder Heads | Summit Racing

Free Shipping - AFR 195cc SBC Enforcer Cylinder Heads with qualifying orders of $109. Shop Cylinder Heads at Summit Racing.

www.summitracing.com

okay so indulge me. If you had a stock 350 TBI and wanted to upgrade it using these heads and keeping TBI, what else would you do on this motor rebuild? @bucket @SquareRoot @AyWoSch Motors give me your hypothicals as well please

 

[SquareRoot]

okay so indulge me. If you had a stock 350 TBI and wanted to upgrade it using these heads and keeping TBI, what else would you do on this motor rebuild? @bucket @SquareRoot @AyWoSch Motors give me your hypothicals as well please

At this point I would realize I've fallen down the rabbit hole. I would ChitCan the whole thing, buy an LS3 and live happily ever after.